Abstract: The Dexing Copper Mine employs FFP1516 40/40 M50 diaphragm filter presses for concen‐ trate filtration. Due to the properties of the slurry，scaling on the filter plates is challenging to remove，se‐ verely affecting filtration efficiency. Improper cleaning methods can even shorten the service life of the filter plates. To address these issues，systematic experimental research and production practices were conducted. Based on the experimental results，the primary component of the scale is calcium hydroxide，along with mi‐ nor amounts of calcium sulfate dihydrate，copper iron sulfide，iron disulfide，and flotation reagents.Compar‐ ative studies on chemical cleaning agents，including industrial hydrochloric acid，slurry cleaning agent KJ- 26，sulfuric acid and ammonia solutions，reveal that KJ-26 achieves effective descaling while being safe and environmentally friendly. Physical removal methods for internal filtrate channel deposits，consisting of hard springs，high-pressure hoses and "soft drill bits" demonstrate that the "soft drill bit" is safe，reliable and highly efficient.By combining chemical immersion with KJ-26 and physical cleaning using the "soft drill bit"，the moisture content of the filter cakes during their lifecycle decreased from 10.8% to 9.9%，reducing transport costs and concentrate leakage. Additionally，the service life of filter plates extended from the de‐ signed 3 years to 4.5 years. This proper cleaning and repair method can save approximately 33，000 RMB per filter plate of operational costs.

Key words: diaphragm filter press, filter plates cleaning, chemical immersion, physical descaling